Object detection method and object detection device
In an object detection method, a moving speed v 0 of a radar device and an angle θ 1 defined between a moving direction of the radar device and a reception direction of a radar wave reflected on a target are acquired, a first function which expresses a relative speed v 1 between the radar device and the target by the speed v 0 and the angle θ 1 in a non-multipath environment model and a second function which expresses the speed v 1 in a multipath environment model are formed, an actual relative speed between the radar device and the target is calculated from a reception signal of the radar wave by using the multipath environment model, and it is determined that the reception signal is derived from a stationary object when a point defined by the θ 1 and the actual relative speed is positioned between the first function and the second function.
1. An object detection method, comprising:
acquiring a moving speed v 0 of a radar device and an angle θ 1 defined between a moving direction of the radar device and a reception direction of a radar wave reflected on a target;
forming a first function which expresses a relative speed v 1 between the radar device and the target by the moving speed v 0 and the angle θ 1 in a non-multipath environment model and a second function which expresses the relative speed v 1 by the moving speed v 0 and the angle θ 1 in a multipath environment model;
calculating an actual relative speed between the radar device and the target from a reception signal of the radar wave reflected on the target by using the multipath environment model; and
determining that the reception signal is derived from a stationary object when a point defined by the angle θ 1 and the actual relative speed calculated in the calculating is positioned between the first function and the second function.
2. The object detection method according to claim 1 ,
wherein the first function is expressed as follows:
v 1 =v 0 ×cos(θ 1 ), and [Expression 1]
[
Expression
2
]
v
1
=
v
0
×
(
cos
(
θ
1
)
+
cos
(
θ
2
)
)
2
wherein an angle θ 2 is defined between the moving direction of the radar device and the target.
3. The object detection method according to claim 2 ,
wherein, in the determining,
a value of cos(θ 2 ) of Expression 2 is fixed to any one value in a range more than or equal to −1 and less than or equal to 1, and
it is determined that the reception signal is derived from the stationary object when the point defined by the angle θ 1 and the actual relative speed is positioned between Expressions 1 and 2.
4. The object detection method according to claim 2 ,
wherein, in the determining,
a value of cos(θ 2 ) of Expression 2 is fixed to 1, and
it is determined that the reception signal is derived from the stationary object when the point defined by the angle θ 1 and the actual relative speed is positioned between Expressions 1 and 2.
5. An object detection device, comprising:
an acquisition part configured to acquire a moving speed v 0 of a radar device and an angle θ 1 defined between a moving direction of the radar device and a reception direction of a radar wave reflected on a target;
a function forming part configured to form a first function which expresses a relative speed v 1 between the radar device and the target by the moving speed v 0 and the angle θ 1 in a non-multipath environment model and a second function which expresses the relative speed v 1 by the moving speed v 0 and the angle θ 1 in a multipath environment model;
a multipath relative speed calculation part configured to calculate an actual relative speed between the radar device and the target from a reception signal of the radar wave reflected on the target by using the multipath environment model; and
a determination part configured to determine that the reception signal is derived from a stationary object when a point defined by the angle θ 1 and the actual relative speed calculated in the multipath relative speed calculation part is positioned between the first function and the second function.